There are three things to look at: 1) consume less resources - when passive ways are there to cool your server room that would allow you to cut back on the coo

There are three things to look at: 1) consume less resources - when passive ways are there to cool your server room that would allow you to cut back on the cooling system 2) seek greener alternative sources - could you supplement your current source of electricity with solar power, even if it is just to reduce your usage of power from less green resources 3) what waste (heat probably) could be used to, for example, heat up the water that is used in the building. Perhaps use it to run a greenhouse for yourself or a charity / community project (good PR that) But first you must be in a position to measure the effectiveness of any solution. Get records of your power usage, preferably by task - how much is used to run the servers, how much to run the cooling etc. Including the cost! Make it more than a PR exercise, you could save some money too (in the long run)